A chip resistor has been widely used for a resistor in view of high density, downsizing and the like of a circuit as an IT (information technology) associated equipment and the like have become recently widespread. A conventional chip resistor comprises, as illustrated in FIG. 6 showing a plan view and FIG. 7 showing a side view, a pair of first electrodes 1 formed by printing a conductive paste comprised of precious metals such as Au, Ag or Au—Pt or comprised of Cu, Al or Ni based material on an insulating substrate 5 (hereinafter referred to as simply substrate 5) made of a material such as alumina, steatite, forsterite and the like by screen printing and the like, and baking the printed conductive paste, and a resistor pattern formed by printing paste for a resistor comprised of a Pd—Ag based or Pd—Ag—RuO2 based material and the like on the thus formed pair of electrodes 1 and baking the printed paste for a resistor so as to extend over the pair of electrodes absorption-type polarizing film 1. Further, an overcoat for protecting the resistor and a side electrode are provided, if necessary.
Since a resistance value of the thus fabricated chip resistor 10 is determined by a sectional area of a resistor film or layer 3 between the pair of electrodes, i.e. the product of a width Y and a thickness Z of the resistor layer 3, i.e. Y×Z and a length X thereof between the pair of electrodes, it is adjusted by reducing a sectional area S1 of the resistor layer 3 so as to obtain a given value in the manner of normally cutting away a part T1 of the resistor layer 3 by computer-controlled laser and the like as shown in FIG. 8.
With the conventional chip resistor 10 having the foregoing construction, the resistor layer 3 is disposed over the pair of electrodes 1 so as to connect therebetween, and the sectional area S1 of the resistor layer 3 between the pair of electrodes 1 taken along a line in parallel with both electrodes is small, and the length X of the resistor layer 3 between the pair of electrodes 1 is longer compared with the thickness thereof. Further, since the entire size of the resistor layer 3 is very small to an extent of about 0.3×0.6 mm, it is convenient for the chip resistor 10 to obtain a high resistance value but it is not easy for the chip resistor 10 to obtain a low resistance value.
Still further, in the case of adjusting a resistance value, trimming is applied to the resistor layer in a linear shape or hooked shape as viewed from a plane thereof shown in FIG. 8 so that the resistance value is controlled by mainly controlling the sectional area S1 (FIG. 8). However, since the sectional area S1 is small, there is a limit to apply trimming to the resistor layer as a matter of course so as to adjust the resistance value, an hence since an adjustable range of the resistance value is small, a given resistance value is not easily obtained.